Mobile communication systems have been developed to provide voice call services, supporting users' mobility. With the development of communication technology, they have recently provided data communication services, or high speed data services. As mobile communication systems evolve to provide more various services, they face lack of resources and users' demands for high speed data services. Therefore, development of more advance mobile communication systems is required.
As smartphones were developed, the mobile traffic has rapidly increased and this causes cellular networks to have difficulty in covering the increase speed of traffic. Wireless LANs (WLANs) that can be established with using unlicensed bands in low cost, as an offloading solution, have again attracted the attention of cellular network operators.
Although most cellular network operators provide services to their subscribers via their directly installed WLANs or in such a way that they are associated with other WLAN operators, they have difficulty in processing traffic of the subscribers in a pace where there is a lot of floating population via only they cellular base stations. In this case, the cellular network operators guide the subscribers to receive services via a WLAN access point.
However, cellular service subscribers who want to use a WLAN access point have been facing difficulty from the moment when they start to search for a WLAN access point to be accessed. As an example of the difficulty, while most cellular service subscribers want to search for only a WLAN access point provided by their cellular network operator, Service Set Identifiers (SSIDs) transmitted from a number of access points surrounding the subscribers are listed on the WLAN access management program of their terminal each time the terminal attempts to search for the corresponding WLAN access point.
This deteriorates user convenience and also causes traffic by the access points that a user do not want to access, thereby deteriorating the quality of WLAN service.